[Wien] How to obtain spin-polarized band gap with spin-orbital coupling?

[lh_yu at sohu.com]

Dear WIEN users:

    I calculated spin-polarized band structure without spin-orbital coupling, the down-bands have an about 1eV gap(up-band is metallic), I want to know the influence of soc on the band gap, add the soc to the convergent sp calculation, it is known that the bands mix up and down electron. Following the guideline of Prof. Blaha (8/6/2010 in mail list), using "fat-bands" plot to show the orbital character. Focusing on the spin down character (seeking down character bands ), I can find the conduction band bottom with clear spin down components, but for the valence band top, the mixture of up and down spin exists obviously.
       
   My questions are:
 (1) Can I use the mixture of up and down spin to obtain or estimate the energy of valence band top for down spin?   
 (2) Can I use the above method to obtain the band gap of down-bands? Is it significant in physics? And if no, How to obtain the band gap with spin-orbital coupling?

Regards,
and thank everyone,

I learn many thing from this maillist, not only method,but also physics. Thank you very much.

Yu Lihua